Traditionally prescription drugs are dispensed by licensed pharmacists who manually count out the number of pills pertaining to a particular prescription and place them in an appropriately labeled container. While direct human counting may ensure a relatively high degree of accuracy, particularly if the count of pills is low, the cost of having a highly-educated and trained professional performing the work adds significantly to the consumer's cost for the drug. Moreover, as the count of pills to be manually placed in a container increases, such as a container having 120 or more pills, for instance, the accuracy may actually decrease with direct human counting.
Mail order drug fulfillment companies and other similar pharmacy operations have become popular in the last ten years or so as consumers and health care insurance providers look for ways of cutting the costs of obtaining prescription drugs. Large drug fulfillment facilities can deliver economies of scale that are just not possible at a local pharmacy.
To further become more efficient and competitive, many large mail order pharmacies have removed the pharmacist from the responsibility of actually counting and dispensing drugs. Rather, the pharmacist's primary duty is to verify that the contents of a filled pill container and its associated label are correct. Accordingly, a much larger volume of prescription orders can be processed by a single pharmacist.
To perform the counting operation, some mail order pharmacies use various pill counter and dispensing devices. These devices usually contain a large number of pills in a storage hopper or other large container and selectively dispense a set number into a smaller container, such as a pill bottle. These devices are often set up in banks in automated drug dispensing arrays that are centrally controlled. Typically, the pill bottle is positioned under a dispensing tube or throat of the device often through the use of automation. Once positioned, the appropriate number of pills is dispensed into the pill bottle. The filled pill bottle may then be sent to a pharmacist to verify that the contents match the container's label and match the Doctor's prescription. No further counting is required by the pharmacist at this point (unless something seem unusual) and the accuracy of number of pills is completely dependent on the method used for counting and dispensing.
There are various ways to count small objects, such as pills, including: singulation (e.g., counting each individual pill), and estimating by mass and/or volume. Given that the densities of prescription drugs can and do often vary from pill to pill, the preferred method of counting is usually singulation. Current dispensing devices typically count each pill as it falls down a chute using a set of opposed and aligned sensors. Essentially, as a pill passes in front of a sensing beam extending between the opposed sensors, a count is registered. Once the desired number of pills have counted and dispensed, the device stops dispensing and the container is forwarded to the pharmacist for verification.
Prior art pill dispensing devices are about 87% accurate with the tendency towards over-counting the actual number of pills actually dispensed. As a result, it is not uncommon for prescriptions to be shipped with several extra pills. This can be costly for high volume mail order pharmacies and similar operations when high value drugs are being dispensed. Additionally, dust and particulate that settles on the surface of the sensors can cause the sensors to malfunction and alter the count of pills. If dust, particulate, or other debris causes a prescription to be under dispensed, a mail order pharmacy may incur a significant customer service expense once the consumer realizes the under count error.
If the discrepancies caused by a particular dispensing device that is not operating properly are relatively small (1-15%), a reviewing pharmacist will not likely catch the under or over count during his/her verification review. As such, the malfunctioning device may continue to operate improperly for extended periods of time. Heretofore, the ability to count and dispense pills with a high degree of accuracy in the context of large volume pharmacy operations does not satisfactorily exist.